Ext 布局问题 下拉框combo

在ext formpanel中使用layout table 布局中出现下拉框和日期框选择项偏离正轴，希望哪位高手能够解决解决，相应的panel代码如下：

var FrPost=new Ext.FormPanel({
     width:'1200',
     title:"ext级联",
     bodyStyle:"padding:5px 5px 0",
     submit: function(){
                     this.getEl().dom.action ='ggg',
                     this.getEl().dom.method='POST',
                     this.getEl().dom.submit();
     },
             buttons:[{
  id:"succss",
  name:"succss",
  type : "button",
       
        text:'提交数据',
        formBind:true,
        handler:function(){
           FrPost.getForm().getEl().dom.submit();  
        }
 },
  {
   name:'submit',
   type : "submit",
   text:'提 交',
   formBind:true,
         handler : function(){
                    FrPost.getForm().getEl().dom.submit();  
          }
  },
  {
   name:'reset',
   type:'reset',
   text:'重 写',
   handler:function(){
    FrPost.getForm().getEl().dom.reset();   
   }
 }]
});     

var formpanel=new Ext.Panel({ 
      layout:"table",
      bodyStyle:'left:0px;top:0px;text-align:center;margin: 0 auto;',
      cls:"center",
      frame:true,
      layoutConfig: {columns:2},
      defaults:

{border:false,layout:'form',frame:false,labelAlign:'right',labelWidth:75,width:'400'}
  });

  FrPost.add(formpanel);
    
         formpanel.add({colspan:1,rowspan:1,items:exttext_0});
       
         formpanel.add({colspan:2,rowspan:8,items:imageext_1});
       
         formpanel.add({colspan:1,rowspan:1,items:extradio_2});
       
         formpanel.add({colspan:1,rowspan:1,items:extdate_3});
       
         formpanel.add({colspan:1,rowspan:1,items:extdate_4});
       
         formpanel.add({colspan:1,rowspan:1,items:exttext_5});
       
         formpanel.add({colspan:1,rowspan:1,items:exttext_6});
       
         formpanel.add({colspan:1,rowspan:1,items:exttext_7});
       
         formpanel.add({colspan:1,rowspan:1,items:extselect_8});
       
        //设置窗口显示大小
        var windowWidth =   window.screen.availWidth;  
       var left=windowWidth/2 - FrPost.width/2;
       var style='margin-top:10px;margin-left:'+left+'px;'; 
       var el=Ext.get('FrPost').applyStyles(style);
        FrPost.render(el);   
 });